SOLUTION: I am having trouble with Graphing the quadratic function f(x)= x^2 + X - 12

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Question 743524: I am having trouble with Graphing the quadratic function f(x)= x^2 + X - 12
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
This one is factorable, making roots easy to find, and making the axis easy to find also.

f%28x%29=x%5E2%2Bx-12=%28x-3%29%28x%2B4%29, so the x-intercepts are x=-3 and x=4. That means, two points of the graph are (+3,0) and (-4,0).

The vertex occurs at x=%283%2B%28-4%29%29%2F2=-1%2F2. We only then need to feed -1%2F2 to f(x) and find the resulting value. y=-12%261%2F4 is this value.

You may then plug in a couple of more points if you want to help show the shape a little better.

graph%28300%2C300%2C-10%2C10%2C-15%2C15%2Cx%5E2%2Bx-12%29